In the automotive industry, the condition of tire treads on tires on a vehicle is important for safety. A new tire on a vehicle, such as a car, typically has a tread depth of 8 mm. As the tire is used, the tread depth diminishes. As the tread depth diminishes, safety risks of driving using those tires increases. For example, when roads are wet, deeper tread depths help channel water away so that the tire maintains contact with the road. This reduces the chances that the vehicle will hydroplane. The risks of worn out tires is also increased in dry weather driving. Since a worn out tire has a lower tread depth, the tire is thinner. A thinner tire increases the chance that the tire will be punctured and cause a tire failure. Not only do deeper tread depths increase safety, but they may also be legally required. For example, in the United States, the minimum legal tread depth is 1.6 mm. Thus, it is useful for a driver to know to the tread depths for the tires on the driver's car.
Previously, however, determining the tread depth was either inaccurate or cost-prohibitive for a home mechanic. One known method to determine if a tire tread is too shallow is the so-called “penny method”. In the penny method, the home mechanic inserts a penny into the tire tread. If the tire tread reaches a certain level on the penny, then tread depth may be sufficient for safe operation. This method is a very rough approximation for tread depth, however. Another method is to use a tread depth gauge. A tread depth gauge may be positioned on a tread to determine tread depth. However, this requires the home mechanic to buy a potentially expensive piece of equipment. Additionally, the tread depth gauge may not be intuitive to use. Another method is to use a high end laser or optical sensor system. However, these systems are generally used in an automotive dealership environment. They may require a significant amount of space and may be cost-prohibitive. Thus, this method would be impractical for a home mechanic.
Accordingly, there is a need for an inexpensive and easy to use system to determine the condition of tire tread depth.